What's the 'Thanks' button all about?

I just pressed it in a thread I started but I don't know what happened.

Seems to be smoe new feature of the forum software that's been slipped in unannounced.

I think it only appears on threads that you start - and allows you to "thank" someone who maybe provides an answer to your question. A post that is "thanked" comes up in a different colour I think.

Pretty useless feature if you ask me, on a discussion board though it could be more useful on a Q+A board